By allowing us to peer into the lives of billions of people, social media has inadvertently created the world’s largest dataset for the measurement of culture. This column argues that by providing quantitative, scalable, high-resolution, and cost-effective measures of revealed cultural distances between populations, it has enormous potential to help social scientists answer some of society’s most pressing issues. These include the persistence of ethnic conflict, the growing fragmentation of society, and the fraying of the social fabric. Cultural distances are also essential to our understanding of trade, migration, and investment flows.